1. Field of the Invention
The present invention relates to a sensor for a magnetic field, and more specifically, to a magnetic field sensor integrated in a semiconductor substrate and a method for fabricating the same.
2. Description of the Related Art
Existence of magnetic energy has been proven through various physical phenomena, and a magnetic field sensor enables a human to indirectly perceive magnetic energy, as it is unperceivable to human sense organs such as eyes and ears. As for the magnetic field sensor, a magnetic sensor employing a soft magnetic material and a coil has been used for a long time. The magnetic sensor is made by winding a coil around a relatively large bar-shaped core or an annular core formed of a soft magnetic ribbon. Also, an electronic circuit is employed to obtain a magnetic field in proportion to the measured magnetic field.
The conventional magnetic field sensor, however, has the following problems. That is, due to the structure of the conventional magnetic field sensor in which the coil is wound around a large bar-shaped core or an annular core made of soft magnetic ribbon, production costs are high, and the volume of the overall system is large.
Also, flux leakage is inevitable in the flux change due to the excitation coil and the detected magnetic field. Accordingly, high sensitivity cannot be guaranteed.